Process for producing compact lacquer layers for record carriers

Abstract

The invention concerns a process for producing compact, cellulose acetobutyrate based lacquer layers with a high degree of dullness for record carriers coated with a metallic or metalliferous layer, wherein high-molecular polysaccharides, having side chains and containing lignin, are admixed with the basic lacquer compound as a filler with a particle size distribution of less than 10 μm and a molecular weight of about 10 6 .

We claim: 
     
       1. A process for producing a record carrier comprising a substrate, an intermediate layer and a metallic or metalliferous overcoat layer, said process comprising the steps of coating the substrate with an intermediate layer which is a cellulose acetobutyrate based lacquer admixed with a filler which is a high-molecular weight polysaccharide having side chains and containing lignin, and having a particle size distribution of less than 10 μm and a molecular weight of about 10 6 , and then coating said intermediate layer with a metallic or metalliferous layer. 
     
     
       2. The process according to claim 1, characterized in that the molecular weight of the filler is chosen so high that it is practically insoluble in acetic esters or solvents for the basic lacquer compound. 
     
     
       3. The process according to claim 1, characterized in using highly crystalline polysaccharides having a plurality of regions with bundles of polysaccharide molecules extending in the same direction. 
     
     
       4. The process according to claim 1, characterized in that as a filler wooden particles are used, wherein the cellulose and the polyose are arranged in very stable microfibrils with diameters of about 20 μm which are interlinked by lignin. 
     
     
       5. The process according to claim 4, characterized in that wood of a deciduous tree with a high original density is used as a filler.